Keyed permutations for fast data scrambling

The hardware design of key-controlled networks that uniformly generate sets of permutations of any even number of inputs is studied. A model is developed in which a necessary and sufficient condition to obtain a one-to-one correspondence between key values and permutations is found. Furthermore the network depth corresponding to the maximum key length matching the condition is determined. An algorithm for designing networks with the stated properties is given and a generalisation to any odd number of inputs is obtained. Copyright © 2005 AEIT.